CalculatorFox

Overview

CalculatorFox is a browser-based calculator library operated by VisibilityOS Network Ltd, a company registered in England and Wales under number 17404974. The site publishes 1,336 calculators organised into 23 categories, spanning mortgage amortisation, payroll withholding, body mass index, concrete volume, tire sizing, unit conversion, statistics, and game damage formulas. Every tool runs in the browser, prints its arithmetic step by step, and lists the references behind its formulas. Accounts are optional for single calculations, while saved scenarios, branded client reports, and embeddable widgets sit across free and paid tiers.

Key Features

A library of 1,336 calculators across 23 categories. Category counts are published openly: Tax, Payroll and Benefits holds 140 tools, Fitness and Nutrition 162, Math and Algebra 109, Loans, Credit and Banking 104, Unit Conversion 103, and Construction and Trades 93. Smaller collections cover electrical work, chemistry, networking, and gaming.

Visible workings on every result. The homepage demonstrates a mortgage payment calculator that breaks a $400,000 purchase with an $80,000 down payment into five ordered steps, moving from loan amount and principal to a final monthly figure of $2,022.62. The steps panel stays open beside the results and recalculates as inputs change.

Cited sources instead of unsourced formulas. The mortgage example attributes its method to HUD Mortgagee Letter 2023-05 and nine additional references, with citation counts listed at page level rather than buried in footnotes.

Free embeddable calculators with hosted starting figures. Three lines of code place a calculator on an external site. The values a calculator opens with, such as an interest rate or a tax band, are stored with the account rather than in the page markup, so a single update propagates to every page showing that widget on the next load. Embeds run without advertising and without tracking readers.

Workspace tiers for saved work. Personal stores scenarios, supports side by side comparison, and allows export and sharing in an ad-free interface. Advisor adds client pages and reports published under a firm's own name, scenarios grouped per client, and a separate embed token, colour, and figure set for each website.

Published governance documentation. Dedicated pages describe the editorial policy for checking calculators, permanent URL guarantees, a changelog, accessibility, security, and licensing.

How It Works

A visitor searches from the homepage box or browses by category, then opens a calculator. The tool presents input fields, a headline result, a breakdown of secondary values, an expandable sequence of calculation steps, and a source list. Guest use requires no registration. Creating an account unlocks scenario saving, comparison, exports, and the embed builder, where starting values and locked fields are configured per embed or per website token.

Who It's For

The library serves general consumers checking loans, dates, and unit conversions; students working through algebra, statistics, and grade averages; small businesses modelling margin, break even, commission, and shipping costs; advisers who need branded reports grouped by client; and publishers who want a calculator widget on their own pages without advertising inside it. Several finance, shipping, and benefits calculators follow United States conventions, which narrows their relevance for audiences elsewhere.